Glossary

Common terms used in game development and Nightshade.

A

Alpha Blending Technique for rendering transparent objects by mixing colors based on alpha (transparency) values.

Alpha Cutoff Threshold for alpha testing. Pixels with alpha below this value are discarded entirely.

Ambient Light Constant, directionless light that illuminates all surfaces equally. Simulates indirect illumination.

Ambient Occlusion (AO) Technique that darkens creases and corners where ambient light would be blocked. See SSAO.

Animation Blending Smoothly transitioning between two animations by interpolating their transforms.

Animation Clip A single named animation (e.g., "walk", "run", "idle") containing keyframed transforms.

Aspect Ratio Width divided by height of the viewport (e.g., 16:9 = 1.777).

B

Billboard A sprite that always faces the camera, commonly used for particles and distant objects.

Bind Pose The default pose of a skeletal mesh before any animation is applied.

Bloom Post-processing effect that creates a glow around bright areas.

Bone A joint in a skeletal hierarchy used for animation. Also called a joint.

C

Cascaded Shadow Maps (CSM) Technique using multiple shadow maps at different resolutions for different distances.

CCD (Continuous Collision Detection) Physics technique to prevent fast-moving objects from passing through thin surfaces.

Character Controller A kinematic physics body designed for player movement with special handling for steps and slopes.

Collider A simplified shape used for physics collision detection (box, sphere, capsule, etc.).

Component Data attached to an entity in an ECS. Contains no logic, only state.

Culling Excluding objects from rendering if they're outside the view or occluded.

D

Delta Time (dt) Time elapsed since the previous frame. Used to make movement frame-rate independent.

Depth Buffer (Z-Buffer) Texture storing the distance of each pixel from the camera. Used for depth testing.

Diffuse The base color of a surface, independent of view angle.

Dynamic Body A physics body affected by forces, gravity, and collisions.

E

ECS (Entity Component System) Architecture where entities are IDs, components are data, and systems are logic.

Emission/Emissive Light that a surface produces itself, independent of external lighting.

Entity A unique identifier that groups related components together. Has no data itself.

Euler Angles Representation of rotation as three angles (pitch, yaw, roll). Can suffer from gimbal lock.

Exposure Brightness adjustment simulating camera exposure settings.

F

Far Plane Maximum distance from the camera at which objects are rendered.

FFT (Fast Fourier Transform) Algorithm to convert audio from time domain to frequency domain.

Field of View (FOV) Angle of the visible area. Typically 60-90 degrees for games.

Forward Rendering Rendering each object completely in one pass. Simple but expensive with many lights.

Frame One complete update and render cycle.

Frustum The 3D region visible to the camera, shaped like a truncated pyramid.

G

G-Buffer Textures storing geometry information (normals, depth, albedo) for deferred rendering.

Gimbal Lock Loss of one degree of freedom when two rotation axes align. Quaternions avoid this.

glTF/GLB Standard 3D model format. glTF is JSON + binary, GLB is single binary file.

Global Transform World-space transformation after parent transforms are applied.

H

HDR (High Dynamic Range) Color values exceeding 0-1 range, allowing for realistic lighting before tonemapping.

Heightfield A 2D grid of height values representing terrain or other surfaces.

Hierarchy Parent-child relationships between entities where child transforms are relative to parents.

I

Index Buffer List of vertex indices defining triangles. Allows vertex reuse.

Instancing Rendering many copies of the same mesh efficiently in a single draw call.

Interpolation Smoothly blending between two values. Linear interpolation (lerp) is most common.

J

Joint Connection point between physics bodies with constraints on movement.

K

Keyframe A specific value at a specific time in an animation. Values are interpolated between keyframes.

Kinematic Body A physics body moved by code that affects dynamic bodies but isn't affected by physics.

L

LDR (Low Dynamic Range) Standard 0-1 color range suitable for display.

Lerp (Linear Interpolation) Blending between two values: result = a + (b - a) * t where t is 0-1.

LOD (Level of Detail) Using simpler meshes for distant objects to improve performance.

Local Transform Position, rotation, scale relative to the parent entity (or world if no parent).

M

Material Defines how a surface looks: color, roughness, metallic, textures, etc.

Mesh Geometry defined by vertices and indices forming triangles.

Metallic PBR property indicating whether a surface is metal (1.0) or dielectric (0.0).

Mipmaps Pre-calculated, progressively smaller versions of a texture for efficient sampling at distance.

Morph Targets Vertex positions for blending between shapes (facial expressions, etc.). Also called blend shapes.

N

NavMesh (Navigation Mesh) Simplified geometry representing walkable areas for AI pathfinding.

Near Plane Minimum distance from camera at which objects are rendered. Objects closer are clipped.

Normal Map Texture encoding surface direction variations to simulate detail without geometry.

O

Occlusion When one object blocks another from view or light.

Orthographic Projection Parallel projection with no perspective. Objects don't get smaller with distance.

P

PBR (Physically Based Rendering) Material model based on real-world physics for consistent, realistic lighting.

Perspective Projection Projection where distant objects appear smaller, simulating human vision.

Pitch Rotation around the X (left-right) axis. Looking up/down.

Point Light Light emitting equally in all directions from a point.

Prefab Pre-configured entity template that can be instantiated multiple times.

Q

Quaternion 4D number representing rotation without gimbal lock. Used for smooth interpolation.

Query Finding entities that have specific components.

R

Raycast Tracing a line through space to find intersections with geometry.

Render Graph Declarative system for defining rendering passes and their dependencies.

Render Pass A single stage of rendering (shadow pass, color pass, post-processing pass).

Rigid Body Physics object that doesn't deform. Can be dynamic, kinematic, or static.

Roll Rotation around the Z (forward) axis. Tilting sideways.

Roughness PBR property controlling how scattered light reflections are. 0=mirror, 1=diffuse.

S

Skinning Deforming mesh vertices based on bone positions. Used for character animation.

Skybox Cubemap texture surrounding the scene representing distant environment.

Slerp (Spherical Linear Interpolation) Interpolation for quaternions that maintains constant angular velocity.

Specular Mirror-like reflection of light. Intensity depends on view angle.

Spot Light Light emitting in a cone shape, like a flashlight.

SSAO (Screen-Space Ambient Occlusion) Post-processing technique approximating ambient occlusion from depth buffer.

Static Body Physics body that never moves. Used for floors, walls, terrain.

System Logic that operates on entities with specific components.

T

Tessellation Subdividing geometry into smaller triangles for detail.

Texture 2D image mapped onto 3D geometry.

Tonemapping Converting HDR colors to displayable LDR range.

Transform Position, rotation, and scale of an object in 3D space.

Transparency See Alpha Blending.

Trimesh (Triangle Mesh) Collision shape using actual mesh geometry. Accurate but expensive.

U

UV Coordinates 2D texture coordinates mapping texture pixels to mesh vertices.

Uniform Shader constant that's the same for all vertices/pixels in a draw call.

V

Vertex Point in 3D space with position, normal, texture coordinates, etc.

Vertex Buffer GPU memory containing vertex data.

Vignette Post-processing effect darkening screen edges.

Vulkan Low-level graphics API. Used by wgpu on Windows/Linux.

W

WebGPU Modern web graphics API. Used by wgpu for cross-platform rendering.

World Space Global coordinate system. Contrast with local/object space.

wgpu Rust graphics library providing cross-platform GPU access.

Y

Yaw Rotation around the Y (up) axis. Looking left/right.

Z

Z-Buffer See Depth Buffer.

Z-Fighting Visual artifacts when two surfaces are at nearly the same depth.